Method of forming inside-boiler-wrapper sheets



Nov 16 1926.

H. M. WOLF METHOD OF FORMING INSIDE BOiLER WRAPPER SHEETS 2 Sheets-Sheet1" Filed August 8 1325 Mr INVENTOR.

ATTORNEY.

-Nov;, 16, 1926. 1,607,377

H.' M. WOLF METHOD FORMI NG INSIDE BOILER WRAPPER SHEETS Filed August 8,1925 2 Sheets-Sheet 2 4 /%wara/ NVEN TOR.

A TTORNEY.

q of sheet 1 and Patented Nov. 16, 1926.

warren STATES PATENT orFicE.

HOVJARB M. VJOLF, OF MUNCIE, INDIANA, ASSIGN OR TO THE BRODERICKCGMPA'NY, A

CORPORATION OF INDIANA.

METHOD OF FORMING INSIDE-BOTLER-WRAPPER SHEETS.

Application filed. August 8, 1925. Serial No. 49,045.

The invention relates to return tubular boilers and has for its objectto produce an inside wrapper sheet comprising a crown sheet and sides orleg elements the rear ends of which extend above the crown sheet,without employing riveted oints and without making in the blank anybends that must again be straightened.

The invention is illustrated in the accompanying drawing in which Fig. 1is a vertical longitudinal section; Figs. 2 and 3 are transversesectional views on lines 2-2 and 3-3 of Fig. 1, respectively; Fig. 4 isa view of a sheet used in forming a certain portion 'ofthe boiler; Fig.5 is the same sheet after a portion has been cut out; and Fig. 6 is thesame sheet after it has been bent into the necessary shape.

The boiler is of the horizontal return tubular type. It has an uppermore or less cylindrical body portion from which extend downwardlylateral and end water legs enclosing a furnace space. The body portionis provided with fire tubes, some of which carry the hot gases forwardinto the front smokebox, the others carrying it from this smokebox backto a rearsmokebox.

The entire boiler illustrated in the drawings is, with the exception ofthe front and rear smokeboxes, to all intents and purposes a singleunitary structure of uniform thickness throughout and without anyriveted or caulked joints.

To provide such a structure I use an outer or main sheet 1, which, aswill be seen particularly from Figs. 2 and 3, is of an inverted U-shape.The middle portion of this sheet forms the upper part of the cylindricalbody and the straight downwardly extending portions form the outside ofthe lateral water legs.

The inner wall or wrapper sheet of the boiler is formed of a secondsheet 2 which also has a generally inverted U-shape except that theupper part is given a reverse downward curve as clearly shown at 3 inFigs. 2 and 3. The straight downwardly extending parts are parallel tothe corresponding parts spaced from them. The bottom of the water legsso formed is closed by portions H of the sheets 2 which are bentoutwardly to meet the lower extremities of thesheet 1. They are weldedto these sheets along the lines 5-5. p

The upper rear part of the inner wrapper This sheet has a straight lowerportion and a curved upper portion. The straight portion is spaced fromthe parallel sheet 13, which closes the rear end of sheet 1 and which iswelded to it along line 11*. The

bottom of the rear water leg thus formed is closed by a bent-overportion 14 of sheet 12, which is welded to 13 along the line 15.

A rear flue sheet is welded to the rear edge of the cut-out portion ofsheet 2, and

to the front edges of sheets 77 and 12. It

is welded to the latter along line 11, and to the sheet 2 along the line11 The front end of sheet 1 is closed by a sheet 16 welded to sheet 1along the line 17. A sheet 18 parallel to 16 and spaced from it closesthe front of sheet 2, being welded to it along the line 19. 'This lowerportion 20 is bent forward to close the lower end of the water leg,being welded to sheet 16 along the line 21.

Through the front water leg extends the short oval thimble 22, formingan opening for firing the boiler, its ends being welded to the edges ofthe holes in the two sheets.

Flues 23 extend from sheet 10 forward we to sheet 16, being rolled orotherwise secured to said two sheets. Flues 24 connect the front sheet16 to the rear sheet 13, being likewise secured to these two sheets byrolling or any other desired method. A front smokebox 25 is secured tosheet 16 in such manner as to cover the forward openings of the fines 23and 24, and a rear smokebox 26 is secured to rear sheet 13 over the rearends of fines 24. The smokebox 26 has an opening 28 for connection tothe stack.

The flat legs around the four sides of the fire box are stayed atintervals by means of the stays 2626. In addition stays 27 connect theflat portion of sheet 1 as shown. The boiler may be used for merelyheating water or for the generation of steam, as desired. The necessaryconnections for introducing water and for taking off the steam ortheheated water will of course be provided.

The products of combustion travel forward through flues 23 and thenbackward through flues 24: into smokebox 26, from which they escapethrough the stack to the connection 28.

In cutting or shaping the parts for the construction of this boiler thepreparation of outer sheet 1 needs no particular mention or description.The sheetQ is cut from a rectangular sheet of the necessary dimensions Aand B, as illustrated in Fig. 4. From this sheet a portion is cut out asindicated at C in Fig. '5. The sheet is then bent so that the portion Eassumes the shape shown in Fig. 6 and the vertical side portions assumeparallel positions as illustrated, the curves at DD being graduallyrounding ones. The bottom portions'44 are turned outwardly at rightangles, the small sheets that form the sides of the upper aux iliarycombustion chamber are then welded to the upper edges of the verticalside portions, just in rear of the crown sheet. It

will thus be seen that no part of this completed inside wrapper sheet isrequired to be bent and then again straightened or flattened in theprocess of producing the sheet.

The remaining sheets are of such simple form that they need no furtherdescription.

he whole structure is assembled and the abutting edges welded byautogenous or other preferred means.

hat I claim is:

The method of forming an inside wrapper sheet for a boiler, whichconsists. in cutting out of a fiat sheet one end of a central panelextending along one of the main axes of the sheet, bending the flatsheet to shape the remaining'portion of said panel into a curved crownsheet andthe side portions of the sheet into parallel legsextending'beyond one end of the crown sheet, and welding a plate to thetop edge of each of the leg extensions to increase the efiectire heightsof such extensions HOWARD M. WOLF.

